I am ashamed of my country — something that I rarely have felt — for withdrawing from the Paris Agreement on climate change. The scientific evidence is overwhelming that greenhouse gas emissions from consumption of fossil fuels endanger the planet and that urgent action is needed. In the Paris accords, 195 nations finally committed to reducing carbon emissions, but now the United States, the richest and most powerful nation, is turning its back on its commitment and on the rest of the world.

Whether other nations will remain committed is uncertain, as is the effect on the United States in the world community.

To be clear, President Trump’s withdrawing from the Paris accords is constitutional. The U.S. agreement to the Paris accords was never approved by the Senate as a treaty. A new president can rescind the executive orders of a predecessor. In fact, even if it were a treaty, the president can unilaterally rescind it.

In the 1970s, President Jimmy Carter rescinded the U.S. treaty with Taiwan as part of recognizing the People’s Republic of China. Arizona Sen. Barry Goldwater sued and argued that this was unconstitutional; he contended that the Senate must approve rescission of a treaty, just as it has to approve the making of a treaty. But the Supreme Court held that the rescission of treaties is left to the political process and not for judicial involvement. Subsequently, President George W. Bush unilaterally rescinded the Anti-Ballistic Missile treaty with Russia.

The fact that President Trump had the constitutional power to withdraw from the Paris accords does not make it desirable or sensible. There is no doubt whatsoever that the planet is warming — sea temperatures are at record highs, year after year sets a new record for the highest average temperature for the planet, the polar ice caps are melting, extreme weather conditions that endanger lives are ever more common. Scientists have conclusively shown that this is a result of greenhouse gas emissions and that reducing them immediately is crucial.

The goal of the Paris agreement is to restrict the global temperature to the 2 degrees Celsius increase that scientists say is the maximum compatible with civilization as we know it, and to aim for the 1.5 Celsius limit that poor and island nations see as crucial for their survival.

Under the accord, the United States had pledged to cut its greenhouse gas emissions 26 to 28 percent below 2005 levels by 2025 and commit up to $3 billion in aid for poorer countries by 2020. The U.S. has contributed more greenhouse gases to the environment than any other nation and remains the world’s No. 2 polluter behind China.

Why then did the United States withdraw from the Paris agreement? President Trump and top-level officials in his administration have denied that climate change is a problem. In the past, Trump repeatedly tweeted that “Global warming is an expensive hoax!” The head of the Environmental Protection Agency, Scott Pruitt, said in March, “I would not agree that it’s a primary contributor to the global warming that we see.”

President Trump, in withdrawing from the Paris accord, said that he wanted to renegotiate a fairer agreement. But that is not going to happen. Within minutes of the president’s remarks, the leaders of France, Germany and Italy issued a joint statement saying that the Paris accord was “irreversible” and could not be renegotiated.

The effects of the U.S. withdrawal from the Paris agreement are unclear. Will this cause other nations to abandon it as well? Even if other nations remain committed to the accord, can it succeed without the participation of the United States? How will the world community react to the United States breaking its commitment? Will this help China, which is rapidly shutting down coal plants and mines and adding solar and wind plants, achieve greater prominence in international affairs? Can the United States still reduce its greenhouse gas emissions, such as through aggressive state and local efforts, without the federal government?

Climate change should not be a partisan issue. In a poll of registered voters taken after the November 2016 election, 69 percent said that the United States should participate in the Paris agreement. This figure included 86 percent of Democrats, 61 percent of Independents and 51 percent of Republicans.

The United States should be the leader in protecting the environment, not the outlier in repudiating an agreement of 195 nations. The withdrawal by the United States is shameful and very frightening for the planet.